Electronic gas-lighting device

ABSTRACT

An electronic gas-lighting device having a casing defined by a cup-shaped body made of electrically insulating material is disclosed. An electronic high-voltage-pulse generator is housed in an inner cavity of the casing accessible through a mouth of the cup-shaped body. An output terminal is connected to the electronic pulse generator and housed through a respective seating duct formed integrally with a bottom wall of the cup-shaped body. A connecting board carrying an electric circuit and extending the full length of the cup-shaped body is positioned substantially closing the mouth, inside the cavity, and carries, on a first face facing the cavity, the electronic pulse generator connected mechanically and electrically to one another and to the board by the board itself and the circuit, so as to be housed in one continuous compartment defined by the inner cavity of the casing and by the connecting board, and so as to be embedded, together with the connecting board, in a matrix of insulating polymer resin which fills the whole of the cavity up to a point flush with the mouth of the cavity. The board has at least one through opening enabling the polymer resin to be poured into the casing with the board already in position.

TECHNICAL FIELD

The present invention relates to an electronic gas-lighting device whichis cheap and easy to assemble and is fittable to a metal conducting bodyelement of an electric household appliance, in particular a cookingrange of a gas cooker, to light the burners.

BACKGROUND ART

Cooking ranges are known featuring integrated electric/electronicgas-lighters which are operated manually by means of pushbuttons togenerate a spark by which to light one of the gas burners on the range.Known gas-lighters comprise a current-discharge generating circuitconnected to one or more output terminals, each of which is connected bya conducting wire to an electrode located close to a burner to be lit:the electrodes are grounded by the range to which they are fitted. Aspark is therefore generated between each electrode and each burnerwhenever a high-voltage current discharge is generated in the circuit.

In a first known type of gas-lighter, the various electric andelectronic components of the circuit are housed in a cup-shaped bodydefining a casing made of nonconducting (typically polymer) material anddivided by an inner wall into a first and second compartment from whichthe supply terminals and output terminals extend respectively; theoutput terminals are connected to respective secondary windings of atransformer in turn connected to a voltage discharger; the windings arehoused in the first compartment of the casing and are embedded in anelectrically insulting polymer resin from which the supply wires of theprimary winding/s emerge; the wires are connected by means of connectorsor soldered to the other circuit components which are normally carriedon a printed circuit together with the components of an electronicfilter, if provided, for filtering any electromagnetic noise producedwhen generating high-voltage pulses; and the printed circuit, togetherwith the electronic components, is housed in the second compartmentwhich is closed by a removable cover.

Devices of the first type therefore take a long time and are expensiveto assemble, on account of the electric connections between thecomponents in the two compartments and the cost of assembling the coveron the second compartment. What is more, in such devices, all thecomponents of the pulse generating circuit (with the exception of thetransformer) are located fairly close to one another and to the supplyterminals.

In a second known type of gas-lighter, the generating circuit isembedded entirely inside a block of polymer resin which thereforesubstitutes for the casing. Nevertheless, this type of device is alsoexpensive to assemble, on account of all the components and respectiveconnecting wires having to be assembled with no support available anddirectly inside the molds into which the resin is poured. As such,devices of this sort are only feasible if cheap labour is available.

DISCLOSURE OF INVENTION

It is an object of the present invention to provide an electronicgas-lighting device of the type described, but designed to eliminate theaforementioned drawbacks, and which, in particular, is easy, fast andcheap to assemble, may even be assembled automatically, and enables theelectronic components to be located a considerable distance from thesupply terminals.

According to the present invention, there is provided an electronicgas-lighting device for spark-lighting at least one respective burner ona cooking range, the device comprising a casing defined by a cup-shapedbody and made of electrically insulating material; electronichigh-voltage-pulse generating means housed in an inner cavity of thecasing, which cavity is accessible through a mouth of the cup-shapedbody opposite and facing a bottom wall of the cup-shaped body; and, foreach said burner catered to, at least one output terminal connected tosaid electronic high-voltage-pulse generating means and housed through arespective seating duct on the casing; characterized by also comprisinga connecting board carrying an electric circuit and extending the fulllength of the cup-shaped body; said connecting board being positionedsubstantially closing said mouth but still inside said cavity, andcarrying, on a first face facing said cavity, all said electronichigh-voltage-pulse generating means connected mechanically andelectrically to one another and to the connecting board by theconnecting board itself and said circuit carried by the connectingboard, so that said electronic high-voltage-pulse generating means arehoused in one continuous compartment defined by said cavity of thecasing and by the connecting board; said electronic high-voltage-pulsegenerating means being embedded, together with the connecting board, ina matrix of insulating polymer resin which fills the whole of saidcavity up to a point substantially flush with said mouth; saidconnecting board having at least one through opening enabling saidpolymer resin to be poured into the casing with the connecting boardalready positioned closing the mouth.

More specifically, the seating duct on the casing projects outwards fromsaid bottom wall of the cup-shaped body, is integral with the cup-shapedbody, and is located on the opposite side to said mouth; and saidelectronic high-voltage-pulse generating means comprise at least onetransformer, in turn comprising a secondary winding on an insulatingtubular support, and a primary winding housed inside the insulatingtubular support and coaxial with the secondary winding; each end of saidsecondary winding being connected to a respective said output terminal,which is defined by a flat blade connector defined by two opposite facesand carried mechanically by said insulating tubular support so that saidfaces are parallel to the axis of said windings.

The connecting board also preferably comprises at least one supplyterminal at a first longitudinal end of the connecting board, located ata first end of said casing; and at least one ground contact at a secondlongitudinal end of the connecting board, opposite the first and locatedat a second end of said casing.

The gas-lighting device according to the invention is thus extremelycompact as compared with similar known devices, while at the same timebeing cheap and easy to produce, easy to assemble, and easy to fit ontothe cooking range, and provides for easily locating a grounded electricor electronic component as far away as possible from the end with thesupply terminals. This is particularly useful, for example, in the eventthe device comprises an electronic noise filter, grounding of which isextremely cheap and easy and involves no complex assembly operations.

BRIEF DESCRIPTION OF DRAWINGS

A non-limiting embodiment of the present invention will be described byway of example with reference to the accompanying drawings, in which:

FIG. 1 shows an exploded top plan view of the gas-lighting deviceaccording to the invention;

FIG. 2 shows a longitudinal lateral section of the FIG. 1 devicepartially assembled;

FIG. 3 shows a top plan view of the FIG. 1 device fully assembled;

FIG. 4 shows a section along line IV—IV in FIG. 3;

FIGS. 5, 6 and 7 show larger-scale schematic sections of respectivedetails of the FIG. 1 device.

BEST MODE FOR CARRYING OUT THE INVENTION

With reference to FIGS. 1 to 7, number 1 indicates as a whole anelectronic gas-lighting device fittable to a known cooking range 2 shownonly partly and schematically for the sake of simplicity.

Device 1 comprises a casing 3 made of electrically insulating material,defined by a cup-shaped body 4, and having an inner cavity 5 housingelectronic high-voltage-pulse generating means 6; and edge 8 ofcup-shaped body 4 defines a mouth 9 enabling access to cavity 5.

In the non-limiting example shown, cup-shaped casing 3 comprises asubstantially rectangular bottom wall 10 opposite and facing mouth 9;and four lateral walls 11, 12, 13, 14 project perpendicularly frombottom wall 10, and define respective outer lateral faces of casing 3and respective portions of edge 8.

Electronic high-voltage-pulse generating means 6 comprise a transformer15 and a voltage discharger 16, both substantially known, and possibly anumber of further known electric or electronic components—not describedin detail for the sake of simplicity—defining as a whole an electrichigh-voltage-pulse generating circuit 17 (operating in known manner).Electric circuit 17 preferably also comprises electromagnetic-noisesuppressing means 18, e.g. a substantially known electronic noisefilter.

Transformer 15 is substantially cylindrical and comprises a primarywinding 21 and two identical secondary windings 22, 23: primary winding21 is wound about a cylindrical core 24 of magnetic material (typicallyferrite); and secondary windings 22, 23 are coaxial and concentric withprimary winding 21, are located radially outwards with respective toprimary winding 21, and are separated longitudinally from each other. Inparticular, secondary windings 22, 23 are wound about respectivesubstantially cylindrical insulating tubular supports 25 made, forexample, of insulating polymer material; and primary winding 21 isinserted coaxially inside tubular supports 25. According to a knownconstruction solution, the turns of secondary windings 22, 23 are housedin a number of annular seats defined by respective radial flanges on theouter lateral surfaces of tubular supports 25, so that tubular supports25 mechanically support both respective secondary windings 22, 23 andthe primary winding 21 inserted inside the tubular supports.

Secondary windings 22, 23 are connected, at respective opposite ends, torespective pairs of output terminals 25, 27, each of which, in use,caters to a corresponding burner on cooking range 2. In particular,output terminals 26, 27 are defined by respective flat blade connectorsmade, for example, of conducting metal and each defined by two oppositefaces 28, 29. According to the invention, connectors 26, 27 are carriedmechanically by tubular supports 25 so that faces 28, 29 are parallel tothe axis of windings 21, 22, 23.

Connectors 26, 27 are housed through respective seating ducts 30 definedby respective tubular projections formed integrally with casing 3 andprojecting perpendicularly outwards from bottom wall 10, on the oppositeside to mouth 9. Close to a first longitudinal end 31 of casing 3,bottom wall 10 also has a further two seating ducts 32 for respectivesupply terminals 33 of electric circuit 17, which may alsoadvantageously be defined by flat blade connectors like output terminals26, 27.

Device 1 also comprises fast-fit means 35 for fitment to a metalconducting body element of an electric household appliance, inparticular to a conducting surface 36 of cooking range 2. In thenon-limiting example shown in FIGS. 1 to 7, fast-fit means 35 comprisetwo click-on connecting elements 37 which are formed integrally withcasing 3, project outwards from lateral wall 11 of casing 3, extendsubstantially parallel to bottom wall 10, and engage respectiveretaining seats 38 formed in conducting surface 36 of cooking range 2.

According to the invention, electric circuit 17 of device 1 is carriedby a connecting board 40 extending the full length of cup-shaped body 4defining casing 3; connecting board 40 is positioned substantiallyclosing mouth 9 of cavity 5, but still inside cavity 5, and defines,together with cavity 5, a continuous compartment 41; connecting board 40carries, on a first face 42 facing cavity 5, electronichigh-voltage-pulse generating means 6 which are therefore all housedinside continuous compartment 41; and electronic high-voltage-pulsegenerating means 6 are connected mechanically and electrically to oneanother and to connecting board 40 by means of connecting board 40itself and electric circuit 17. In the non-limiting example shown inFIGS. 1 to 7, connecting board 40 is a flat rectangular board insertedinside cavity 5 of casing 3, parallel to bottom wall 10 of casing 3, andwith first face 42 facing bottom wall 10.

Electronic high-voltage-pulse generating means 6 and connecting board 40are embedded in a matrix 43 of insulating polymer resin which fills thewhole of cavity 5 up to a point substantially flush with mouth 9. Toenable the polymer resin to be poured into cavity 5 with connectingboard 40 already positioned closing mouth 9, connecting board 40 has athrough opening 44 of any shape, and a number of through holes 45located away from through opening 44: through opening 44 thereforeenables the polymer resin to be poured into cavity 5 through connectingboard 40, while through holes 45 provide for expelling air fromcontinuous compartment 41 as the polymer resin is being poured.

Electronic high-voltage-pulse generating means 6 are therefore housedinside continuous compartment 41 and embedded in polymer resin matrix43. In particular, transformer 15 and voltage discharger 16 aretherefore also located on the same side of connecting board 40, betweenconnecting board 40 and bottom wall 10 of casing 3; and voltagedischarger 16 projects perpendicularly from first face 42 of connectingboard 40 towards bottom wall 10, and is partially housed in a respectivesemicylindrical seat 46 projecting from bottom wall 10, on the outsideof casing 3, and defining a semicylindrical projection on bottom wall10.

Supply terminals 33 of electric circuit 17 are located at a firstlongitudinal end 47 of connecting board 40, located at longitudinal end31 of casing 3; connecting board 40 also comprises a ground contact 50at a second longitudinal end 48 of the connecting board, opposite firstlongitudinal end 47 and located at a longitudinal end 49 of casing 3;transformer 15 is located close to longitudinal end 48 of connectingboard 40 having ground contact 50; and voltage discharger 16 is locatedclose to longitudinal end 47 of connecting board 40, between transformer15 and supply terminals 33, and substantially alongside supply terminals33.

Ground contact 50 extends through polymer resin matrix 43, on theopposite side to bottom wall 10. In the preferred embodiment shown,ground contact 50 is connected to a generic component 51 of electriccircuit 17, which in turn is connected mechanically and electrically toface 42 of connecting board 40. Ground contact 50 extends, throughthrough opening 44 in connecting board 40, astride edge 8 defining mouth9, and more specifically astride the portion of edge 8 defined bylateral wall 11 of casing 3. In particular, ground contact 50 has an endportion 52 projecting outside continuous compartment 41 and outsidematrix 43, and which is positioned parallel to an outer lateral surface53 of casing 3, for example, an outer surface of lateral wall 11, sothat end portion 52 of ground contact 50 is available externally onlateral wall 11 of casing 3, on the same side as click-on connectingelements 37, and is gripped, in use, between casing 3 and conductingsurface 36 of cooking range 2 to rapidly ground connecting board 40, andin particular component 51, as shown schematically in FIG. 5 (in whichthe components shown are not accurately proportioned).

Ground contact 50 may, of course, be connected to conducting surface 36of cooking range 2 otherwise than as described above, e.g. using aconnecting element of any known type fitted to the free end of endportion 52 and which clicks inside a respective seat on cooking range 2.

Component 51 of electric circuit 17, to which ground contact 50 isconnected, is advantageously a component of electronic noise filter 18,e.g. a capacitor (which, according to one known solution, needsgrounding). By virtue of the conformation of device 1 according to theinvention, ground contact 50 is located as far as possible from supplyterminals 33.

Moreover, tubular supports 25 of transformer 15, which mechanicallysupport both secondary windings 22, 23 and primary winding 21, arepreferably connected integrally and removably to connecting board 40,e.g. by means of a number of fastening pins 54 inserted insiderespective holes 55 on connecting board 40. The opposite ends of primarywinding 21 are also connected electrically to electric circuit 17, inany known manner, by means of a pair of insulated electric conductors 56in turn connected electrically and mechanically to respective connectingterminals 57 on connecting board 40.

For example, insulated electric conductors 56 are conducting wiressurrounded with insulating material, and connecting terminals 57 aredefined by respective blade contacts projecting from a second face 58,opposite first face 42, of connecting board 40 and having respectiveV-shaped notches with cutting edges: when the respective ends ofinsulated electric conductors 56 are pressed into the V-shaped notchesof the blade contacts, the cutting edges of the notches cut the endspartly and deep enough to expose the respective conducting wires inside.

Insulated electric conductors 56 may, of course, be connected toconnecting terminals 57 in any other known manner, e.g. by soldering.

Clearly, further changes may be made to the device as described abovewithout, however, departing from the scope of the accompanying Claims.

What is claimed is:
 1. An electronic gas-lighting device forspark-lighting at least one respective burner on a cooking range, thedevice comprising a casing defined by a cup-shaped body and made ofelectrically insulating material; electronic high-voltage-pulsegenerating means housed in an inner cavity of the casing, which cavityis accessible through a mouth of the cup-shaped body opposite and facinga bottom wall of the cup-shaped body; and, for each said burner cateredto, at least one output terminal connected to said electronichigh-voltage-pulse generating means and housed through a respectiveseating duct on the casing; characterized by also comprising aconnecting board carrying an electric circuit and extending the fulllength of the cup-shaped body; said connecting board being positionedsubstantially closing said mouth but still inside said cavity, andcarrying, on a first face facing said cavity, said electronichigh-voltage-pulse generating means connected mechanically andelectrically to the connecting board and said circuit carried by theconnecting board, so that said electronic high-voltage-pulse generatingmeans is housed in one continuous compartment defined by said cavity ofthe casing and by the connecting board; said electronichigh-voltage-pulse generating means being embedded, together with theconnecting board, in a matrix of insulating polymer resin which fillsthe whole of said cavity up to a point substantially flush with saidmouth; said connecting board having at least one through openingenabling said polymer resin to be poured into the casing with theconnecting board already positioned closing the mouth.
 2. A device asclaimed in claim 1, characterized in that said seating duct on thecasing projects outwards from said bottom wall of the cup-shaped body,is integral with the cup-shaped body, and is located on the oppositeside to said mouth; and in that said electronic high-voltage-pulsegenerating means comprise at least one transformer, in turn comprising asecondary winding on an insulating tubular support, and a primarywinding housed inside the insulating tubular support and coaxial withthe secondary winding; each end of said secondary winding beingconnected to a respective said output terminal, which is defined by aflat blade connector defined by two opposite faces and carriedmechanically by said insulating tubular support so that said faces areparallel to the axis of said windings.
 3. A device as claimed in claim1, characterized in that said connecting board comprises at least onesupply terminal at a first longitudinal end of the connecting board,located at a first end of said casing; an at least one ground contact ata second longitudinal end of the connecting board, opposite the firstand located at a second end of the said casing.
 4. A device as claimedin claim 3, characterized in that said ground contact extends throughsaid matrix of polymer resin, on the opposite side to said bottom wall,and has an end portion projecting outside said continuous compartmentand outside said matrix of polymer resin; said end portion of saidground contact being positioned parallel to an outer lateral surface ofsaid casing.
 5. A device as claimed in claim 4, characterized in thatsaid ground contact extends through said through opening in theconnecting board and astride an edge of said mouth.
 6. A device asclaimed in claim 4 characterized by also comprising fast-fit means forfitment to a metal conducting body element of an electric householdappliance, in particular to a cooking range of a gas cooker; saidfast-fit means comprising respective click-on connecting means which areformed integrally with said casing, project from a lateral wall of saidcup-shaped body defining the casing, and extend substantially parallelto said bottom wall; said end portion of the ground contact beingavailable externally on said lateral wall of the casing, on the sameside as and between said click-on connecting means, and being gripped,in use, between said casing and a conducting surface of said metalconducting body element of an electric household appliance to rapidlyground the connecting board.
 7. A device as claimed claim 1characterized in that said connecting board comprises, in combination,at least said through opening, and at least one through hole locatedapart from said through opening and by which air is expelled from saidcontinuous compartment as the continuous compartment is filled with saidresin to form said matrix.
 8. A device as claimed in claim 2,characterized in that said electronic high-voltage-pulse generatingmeans also comprise a voltage discharger which projects perpendicularlyfrom said connecting board towards said bottom wall, and is housedpartially in a semicylindrical seat defining a semicylindricalprojection on the outside of said bottom wall.
 9. A device as claimed inclaim 3, characterized in that said electronic high-voltage-pulsegenerating means comprise an electronic electromagnetic-noise filter;said ground contact being connected to a component of said electronicelectromagnetic-noise filter connected mechanically and electrically tosaid connecting board.
 10. A device as claimed in claim 2, characterizedin that said insulating tubular support mechanically supports both theprimary and secondary windings, and is connected integrally andremovably to said connecting board by at least one respective fasteningpin; the opposite ends of the primary winding being connectedelectrically to said electric circuit on the connecting board by twoinsulated electric conductors connected electrically and mechanically torespective connecting terminals on the connecting board.
 11. A device asclaimed in claim 10, characterized in that said insulated electricconductors are soldered to said connecting terminals.
 12. A device asclaimed in claim 10, characterized in that said terminals to which saidinsulated electric conductors are connected are defined by respectiveblade contacts projecting from said first face of the connecting boardand having respective V-shaped notches into which respective ends of theinsulated electric conductors are pressed so as to be cut partially byrespective cutting edges of the notches to a depth sufficient to exposerespective conducting wires.